1. Field of the Invention
This invention relates to antijackknifing devices attached to a trailer. More particular, an antijackknifing device is disclosed which acts between first and second serially towed trailers. The device herein disclosed is to be distinguished from those antijackknifing devices which act between a towing tractor on one hand and the first towed trailer on the other hand.
The term "jackknifing" refers to a common accident occurring between a towing vehicle and a towed vehicle. Specifically, when the towing vehicle comes to an abrupt halt, the towed vehicle frequently overtakes the towing vehicle. In such overtaking action, the towed vehicle typically changes its relative angular alignment with respect to the towing vehicle. For example, a truck trailer which normally occupies one lane suddenly becomes angularly askew with respect to the roadway and occupies several lanes with great suddenness. Collisions with adjacent and following vehicles occur. Frequently upsetting of the truck and trailer results. Serious injury can follow.
2. Brief Description of the Prior Art
Antijackknifing devices between a towing powered tractor and the first following and towed tailer are quite well known. Examples of such devices may be found in Herbert U.S. Pat. No. 3,722,919, Hubbert U.S. Pat. No. 4,252,336, Hayes et al. U.S. Pat. No. 3,874,699, Myers U.S. Pat. No. 4,068,860, Koroknay et al. U.S. Pat. No. 4,109,929 and Herbert U.S. Pat. No. 4,438,943.
It has become increasingly common, particularly in the Western United States, for tractors to tow more than one trailer. When more than one trailer is towed, there are multiple points of interconnection where jackknifing can occur. These multiple points are located at articulating interfaces other that the interface between the powered towing tractor and the first trailer. Accordingly, there exists a need for antijackknifing devices at articulating interfaces other than those between the tractor and the first towed trailer.
In order to make clear the following description, terminology must be defined. In this specification I will refer to the "towing trailer" as that trailer which is nearest the powered tractor. I will refer to the towed trailer as that trailer which is serially pulled by the towing trailer.